Group consisting of the four seiyuu: Haruka Tomatsu, Minako Kotobuki, Ayahi Takagaki and Aki Toyosaki.

They currently have released 19 singles and 4 albums, and one best album. On November 23, 2010 Sphere performed at Nippon Budokan. They celebrated their 5th anniversary in Nippon Budokan, and had their Eternal Live Tour 2014 in Makuhari Messe. In 2015 they held their Sphere BEST Live in Yoyogi 1st Gymnasium, and the following year, held Sphere Fes. Sphere Fes was a 6 hour event for 2 days. Last July 2016, they performed in Anisong World Matsuri in LA. Another Live event was held on March 2017.